The daughter of admiral Dwight Greenhill, Frederica Greenhill (Japanese: フレデリカ・グリーンヒル) was the Salutatorian graduate from Free Planets Alliance Officer Academy, graduating in Space Era 794. She served as Yang Wen-li's aide in the FPA's 13th Fleet, and later became his wife. She is known to have perfect memory, allowing her to recall with crystal clarity details from events decades in the past.
In Imperial Year 479, when she was 14 years old, Frederica Greenhill was on the planet El Facil with her mother, visiting family, when the star sytem was invaded by the Galactic Empire. On El Facil, the higher-ranking FPA officers fled, leaving the young LtJG Yang Wenli in charge of the evacuation effort: once, Frederica brought Yang some coffee in a paper cup when he was choking on a sandwich. After he hand drunk the coffee, Yang told her, "I hate coffee. I wish you'd given me tea." Yang would apologize for his rude comments when the two met again, eight years later.
Thanks to Yang Wen-li's efforts, Frederica and her mother, along with several million other civilians, were successfully able to escape El Facil before the Imperial forces occupied the planet.
After the Battle of Astate, Yang Wen-li was given command of the newly-formed 13th Fleet. Admiral Alex Cazelnu assigned Frederica Greenhill as Yang's personal aide. At the time, Frederica held the rank of Lieutenant, Junior Grade. She served in this role for three years until after the Battle of Vermillion, even during the National Salvation Military Council coup which placed her in opposition to her father. Shortly before the Battle of Vermillion, Yang proposed to her and she accepted.
Frederica and Yang resigned from the Fleet after the Alliance's surrender and married shortly afterwards.
Although Yang anticipated several years of peace, it was less than a year before the Alliance, under pressure from Reinhard's Consul, arrested him. Frederica participated in Yang's rescue, personally shooting an Alliance officer who attempted to execute her husband, and subsequently resumed her role as Yang's adjutant through the following campaign.
After the Battle of the Corridor Frederica fell ill due to fatigue and was confined to bed, preventing her from accompanying Yang when he travelled to negotiate with Reinhard von Lohengramm. After Yang's assassination Frederica accepted the role of political representative for the Yang Fleet and supported Julian Mintz as the military leader although she stated she would rather had democracy die than Yang.
"I clearly remember a young Lieutenant taking command... gnawing a sandwich because he didn't have the spare time to eat."